J-pole antenna

• US 20090102737A1
• Filed: 03/30/2007
• Published: 04/23/2009
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Itron Networked Solutions, Inc. (Itron, Inc.)
• Original Assignee: Silver Spring Networks, Inc. (Itron, Inc.)
• Inventors: Gilbert, Brad, Mabry, Thomas, Birnbaum, Thomas
• Granted Patent: US 7,859,477 B2
• Time in Patent Office: Days
• US Class Current: 343/828
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

A J-Pole antenna disclosed including: shunt segment extending out of the plane of the J-Pole antenna. A shunt segment extending out of the plane of the J-pole antenna aids in attaching the antenna to a connector and allowing for a reduction in the size of the antenna and connector. The shunt segment also makes the antenna shorter while preserving the same gain and impedance performance as a conventional J-Pole antenna. A connector plate and connector may be used with the antenna having the shunt segment extending out of the plane of the J-Pole antenna. A protective enclosure may be used with the J-Pole antenna and allowing a radiating antenna segment of the J-Pole antenna to extend from the protective enclosure.

Claims

1. An antenna for use in an RF communications network, comprising:

a connector including a feed line and a ground line, and

an antenna segment formed from a single conductive material and securely connected to the connector, the antenna segment formed to include;

a radiating antenna segment, the radiating antenna segment electrically connected to a feed line,

a non-radiating matching segment substantially parallel to the radiating arm, the non-radiating matching arm substantially shorter than the radiating segment, the non-radiating matching segment electrically connected to the feedline at the first part of the matching segement, blow the radiating segment), and ground line at the other part or arm of the matching segment, and

a shunt segment electrically connected to the non-radiating matching segment, the shunt segment formed between the feed line connection point and the ground line connection point,

wherein the shunt segment is positioned to not extend below the connection point of the feed line to the radiating antenna segment.

2. The antenna of claim 1, wherein the shunt segment is formed as a bend in the conductive material.

3. The antenna of claim 1, further comprising a connector plate, providing the ground, and that provides a secured opening for the feedline connector, but electrically isolated from the feedline.

4. The antenna of claim 3, wherein the connector is a coaxial type connector.

5. The antenna of claim 4, wherein the shunt segment is formed as bend in the conductive material extending away from the connector plate.

6. The antenna of claim 5, wherein the shunt segment forms a loop which is substantially parallel to the radiating antenna segment and the matching segment.

7. The antenna of claim 3, further comprising an antenna enclosure attached to the connector plate and formed to enclose the matching segment, the antenna enclosure including a radiating antenna segment opening positioned to allow the radiating antenna segment to extend from the antenna enclosure.

8. The antenna of claim 1, wherein the radiating antenna segment is a telescoping segment.

9. The antenna of claim 7, wherein the radiating antenna segment is a removable segment.

10. The antenna of claim 1, further comprising an electronic device enclosure attached to the antenna and formed to enclose the matching segment and an electronic device, the antenna enclosure including a radiating antenna segment opening positioned to allow the radiating antenna segment to extend from the antenna enclosure.

11. The antenna of claim 10, wherein the radiating antenna segment is a foldable unit and includes a pivot joint securely attached between an upper radiating segment and a lower matching antenna segment such that the upper radiating segment may be moved between a position in line with the lower matching segment and a position out of line with the lower radiating segment.

12. The antenna of claim 10, wherein the radiating antenna segment includes a removable segment.

13. A J-Pole antenna comprising:

a radiating antenna segment connectable to a feed point at a suitable point in the lower section of the matching segment;

a parallel arm of matching segment connectable to a ground at a point that provides suitable matching impedance;

a shunt segment connected between the connection the antenna to the feed point and the matching segment connection to a ground point, wherein at least a portion of the shunt segment is positioned to extend away from the plane formed by the radiating antenna and the matching segment.

14. The J-Pole antenna of claim 13, wherein a portion of the shunt segment forms a loop parallel to the plane formed by the radiating antenna segment and the matching segment.

15. The J-Pole antenna of claim 14, wherein the J-Pole antenna is formed from a single piece of conductive tubing.